Mechanism for timing the operations of concrete-mixing and other machines



July 3, 1928. 1,675,733

s. SHAFER, JR MECHANISM FOR TIMING THE OPERATIONS OF CONCRETE MIXING AND OTHER MACHINES Patented July 3, 1928.

UNITED STATES PATENT OFFICE.

SAMUEL SHAFER, JR., OF MILWAUKEE, WISCONSIN, ASSIGIN'OR TO CHAIN BELT COM- PANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

MECHANISM FOR TIMING Tim OPERATIONS on CONCRETE-MIXING AND ornnn MACHINES.

Application filed September 16, 1926. Serial No. 135,909;

This invention relates generally to mechanism for timing mechanical operations, and more especially to mechanism connected and combined with apparatus of the type illustrated by power-driven concrete mixing machines.

In the accompanying drawings Fig. 1 is a side view largely diagrammatic in character, of a concrete paving machine, illustrating my invention adapted thereto.

Fig. 2 is a diagrammatic side elevation illustrating the invention, on a larger scale than Fig. 1.

Many of the parts of the paving machine represented in the drawings have been omitted to simplify the illustration of the invention, and as the omitted parts have no essential connection with the invention.

Referring to the drawings, A indicates a rotating mixing drum suitably mounted upon a supporting base which is represented as being movable.

B indicates the charging skip or loader for the drum, pivotally supported at b; and C the discharge chute through which the material mixed and treated within the drum is delivered. The latter is of the power-driven type, the mechanism for controlling and moving it being mounted within a casing D. This mechanism may be like that illustrated in Patent 1,415,411 of May 9, 1922, granted on an application filed by me, and therefore need not be herein illustrated in detail, it being deemed sufficient to show only the exposed handle F by which the operating mechanism within the casing D is controlled and put into connection with the power shaft that operates it.

E represents a casing enclosing a batch timing mechanism. This mechanism may be variously constructed, that which I prefer to use being described and claimed in a copending application filed by me April 30, 1926, and bearing Serial Number 105,798, of which application this case is a division. Sufiiee it here to say that this timing mechanism is arranged to be intermittently operated and when set into motion runs for a predetermined period of time. It is arranged to be set, but not started into motion, when some operation of the apparatus being timed takes place, as for instance when the opera tor moves the lever to cause the loading skip to be raised to charging position; but the tim ng mechanism is not put into motion until everything is fully ready for that operation to commence. In other words the setting of the timing mechanism and the starting thereof are distinct operations with a variable interval of time between them. The setting mechanism and the, starting mechanism, controlling the timing mechanism, are represented as both under manual control.

The timing mechanism is also represented as being arranged to lock the discharge chute in its delivery position during the period it is in operation, andto release the discharge chute at the close of the timed period.

45 indicates a manually operated lever, conveniently located at the side of the machine and arranged to control the clutch Gr by which the drum, on which is wound the hoisting cable for the charging skip, is put into connection with the power shaft that drives it. These are well known features in common use on concrete mixing machines and need not be further described.

46 is a manually controlled lever by which the brake H that controls the downward movements of the loading skip is operated, such lever being mounted in proximity to the lever 45 so that an attendant can conveniently attend to and manipulate both. This feature is also in common use on concrete mixing machines.

As represented the lever 45 carries a contact part 55 that is adapted to engage with an adjustable nut 50 upon a rod 49 that is connected with a bell crank lever 48, which in turn is connected by alink 47 with the set lever 2 of the timing mechanism. It will be seen that the arrangement of linkage between the lever 45 and the set armor lever 2 of the timing mechanism operates to move said set arm to the left from the position indicated in the drawing whenever the hoist lever 45 is moved in the direction of the arrow 00, and that such movement of the lever will cause the hoisting cable-to be wound upon its drum and the skip to move to charging position, and the timing mechanism to be set-that is to say, put into a condition to be ready to begin a timing operation.

51 indicates a latch located in the path of movement of the collar 50 upon the rod 49, and arranged to engage with such collar and hold the rod and the parts of the linkage described in the positions to which they are moved when the hand lever 45 is moved to cause the lifting of the loading skip. spring 53 acts upon the latch 51, holding it in the path of the collar 50. It will be thus seen that when the lever 45 is moved to cause the skip to be elevated to charging position, and the timing mechanism is set, that the timing mechanism becomes locked in its set position and thus held until released by mechanism independent of the lever 4a, which is then free to return to normal pos1- tion irrespective of the linkage connected with the timing mechanism.

The brake control'lever 46 is connnected by a link 5 1 with a bell crank lever 52, the free end of which is arranged to act upon and move the latch 51. It will be seen that when the brake control lever is moved in the direction of the arrow 1 as when the brake H is released to permit descent of the loading skip from its charging position, that the bell crank lever 52 will be moved so as to retract the latch 51 and cause it to disengage the collar 50, thus freeing the timing mechanism, which thereupon immediately begins its timingoperation, moving the set arm 2 and the linkage connected therewith toward their normal positions, and immediately carrying the collar beyond the range of the latch 51.

From this it is apparentthat whenever the mixing drumis charged, this being a manually controlled operation, the timing mechanism is set, and is locked in such set position, leaving the mechanism that controls the drum-charging mechanism free; and that as soon as the ski begins to descend, though the manipulatlon of the lever 16, the timing mechanism is freed and begins its operation. The return or lowering of the charging skip, in the practical operation of a concrete mixing machine, 'takes place as soon as it is manually practicable after the com lete charge has been delivered from the skip into the drum. In other words the loading skip begins its descent and the timing mechanism is freed as soon as the entire charge of material has: been delivered to the drum, and the timing operation does not begin until the full charge has been delivered to the drum, as indicated by the commencement of the downward movement of the loading skip. It sometimes is found necessary to maintain the loading skip in its elevated or char ing position for an appreciable length of time, and with batch meters as now commonlyconstructed and operated where the batch meter is set and released 1) the upward movement of the chargin s ip, this period, during which the skip is held in elevated position, is included within the time measured by the batch meter, notwithstanding the fact that the full charge may not have been delivered to the drum. Indeed the reason for maintaining the charging skip in an elevated position for some appreciable length of time is usually because it is found that for one reason or another the full charge has not been delivered -to the mixing drum immediately upon the skip coming to its charging position. By my invention, however, the starting of the operation of the batch timer, prior to the delivery of the full charge to the drum, 1B prevented, because the batch meter or timing mechanism is not started into operation until the skip starts on its downward return movement, and this, being manuallycontrolled, does not take place until the complete charge has been delivered to the drum. It may be thatby the arrangement described the batch or the major part thereof, will be within the drum for a somewhat longer time than that measured'by the timing mechanism, but a longer mixing of the material within the drum is not objectionable; whereas a mixing for ashorter time than is determined by the timing mechanism is objectionable, impairing the quality of the material delivered from the drum, and, under governmental regulations and stipulations of contracts, subjecting the user of the machine to penalties.

It will be seen by reference to the drawings that the batch timing mechanism within the casing E is mounted in close proximity to the power-driven mechanism that operates the delivery chute, located within the casing D. This permits the locking rod 17 of the timing mechanism to act directly upon an arm connected with the control handle F for the mechanism that operates the discharge chute. The locking rod 17 occupies the position represented in full lines Fig. 2 when the dischar e chute is in operative or delivery positiombut when the mechanism within the casing D is moved to carry the discharge chute to the non-delivery position, shown by dotted lines, the locking rod moves downwardly and its end comes into engagement with the arm 60. It, now, the timing mechanism is set, the rod 17 is locked and t e discharge chute is locked in non-delivery position, and it is so held until the timing mechanism completes its cycle of movements, indicating, usually by the sounding of a bell 41, that the mixin or other operation taking place within t e drum has continued forthe length of time determined by the timing mechanism. This locking of the dischar e chute in non-delivery position, by the timing mechanism or batch meter, while it is in operation, is a well known feature and may be carried out by a wide variety, of mechanisms and, as the specific to'the face of the casing D and arranged to' be acted upon by a pin 62 carried by' an eccentric or cam 61 that is supported upon the shaft h of the power operating mechanism for the discharge chute. lVhen such mechanism is moved to put the chute into delivery position, indicated by full lines Fig. 2, the cam 61 occupies the position indicated by full lines, elevating the tappet arm 63 and the locking rod 17, in which position the latter cannot be locked; but when the parts of the driving mechanism are moved to shift the delivery chute into its inactive or non-delivery position, represented in dotted lines, Fig. 2, the cam occupies a position that permits the rod 17 to move downwardly and lock the discharge chute as soon as the timing mechanism is set.

What I claim is:

1. In a machine whose operations are to be timed, the combination with a charging means for the machine, of a timing device arranged to be set and to run for a determined time when released, means, manually operated, for controlling themovements of the charging means to deliver its charge and setting the timing device, and means, also manually operated, for controlling the return movements of the charging meahs and releasing the timing device.

2. In a machine whose operations are to be timed, the combination with a charging means therefor, of a timing device arranged to be set and to run for a determined period of time when released, manually operated means controlling the movement of the charging means to delivery position, arranged to set the timing device, and other manually controlled means for governing the movement of the charging means after delivery, arranged to release the timing device.

3. The combination with mechanism whose operations are to be timed, of a timing device arranged to be set and ,to run for a determined period. of'time when released, manually controlled means arranged to set charged, of a member functioning the discharge chute, means for tlming the the timing device, and other manually con trolled means appurtenant to the operation of said mechanism for releasing the timing device.

4. The combination with a receptacle, and a chute by which the receptacle is dis to lock operations taking place within the receptacle arranged to be set and to run fora determined period when released, and means for releasing the discharge chute from said locking member, the releasing operation being incident to normalizing the timing device.

5. In combination with a receptacle and a chute through which it is discharged, of a member arranged, when left free, to assume a position to lock the discharge chute, means for timing the operations taking place within the receptacle arranged to be set and to run for a determined period when released, and means to move the locking member to free the discharge chute, o erated when the timing device is normalize and released so as to function to lock the discharge chute when the timing device is released and begins its timing operation.

6. The combination with a receptacle whose operations are to be timed, a charging mechanism therefor, a manually operated lever controllin the lifting of the charging mechanism, an a manually operated brake lever for controlling the lowering of the charging mechanism, of a timing device adapted to be set and when released to operate for a determined period, means connected with the manually operated lever that controls the lifting of the charging mechanism for setting the timing device, and means connected with the brake lever for releasing the timing device.

7. The combination with a rece tacle whose operations are to be timed, of a timin device adapted to be set and when released to run for a determined period, a hand lever appurtenant to the said receptacle for setting the timing device and a second hand lever appurtenant to the receptacle for releasing the timing device.

SAMUEL SHAFER, JR. 

